Depends on your fitness and lines. There's a few short, steep climbs. I have a single up front and an 8 speed cassette, I can ride most of the trail in 32/18 without much trouble. When it's muddy some of the climbs give me a hard time and I have to drop into a lower gear.
There's a handful of singlespeeders on our trails. I saw someone on ss vassago last weekend.
Its not the best for singlespeed but its fun. I currently run a 32x18 but will be trying out a 16 cog in the back next week. The only obstacles to a singlespeed are quite a few flat spots and very steep very short climbs that can be frustrating.